Lactones

Five-membered-ring lactones of beetles, and the special case of epilach-nine, a large-ring lactone with a nitrogen in the ring, have been described. Large-ring lactones or macrolides are relatively common in insects. The Amitermes group of termites use lactones in their defensive secretions. 15-Pentadecanolide, 21-heneicosanolide, 22-docosanolide and

(Z)-3-hexenol (£)-3-hexenol (£)-2-hexenal 1 -octen-3-o!

Figure 3.36 The formation of some of the 'green leaf volatiles' by plants and used by some insects. The biosynthesis in insects may not be by the same route, l-octen-3-ol is from a millipede but of unknown biosynthetic origin

(Z)-3-hexenol (£)-3-hexenol (£)-2-hexenal 1 -octen-3-o!

Figure 3.36 The formation of some of the 'green leaf volatiles' by plants and used by some insects. The biosynthesis in insects may not be by the same route, l-octen-3-ol is from a millipede but of unknown biosynthetic origin